/*
 * Copyright 2010 Yannick Stucki (yannickstucki.com)
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * 
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.yannickstucki.android.musicqueue.communication;

import java.util.LinkedList;

import com.yannickstucki.android.musicqueue.data.Song;

/**
 * A screen mode can provide a this listener to react to music play back
 * changes.
 * 
 * @author Yannick Stucki
 * 
 */
public interface OnUiUpdateListener {

  /**
   * A song started playing.
   */
  void play();

  /**
   * A song has been paused.
   */
  void pause();

  /**
   * Sets the displayed songs.
   */
  void setDisplayedSongs(Song[] displayedSongs);

  /**
   * Notifies that the displayed songs have changed.
   */
  void onDisplayedSongsChanged();

  /**
   * Notifies that a song has been pushed to fill the gap at the end of
   * displayed songs.
   */
  void onDisplayedSongPushed();

  /**
   * Sets the queue.
   */
  void setQueue(LinkedList<Song> queue);

  /**
   * Notifies that the queue has changed.
   */
  void onQueueChanged();

}
